Railway cars having three or more trucks, such as articulated railway cars, have become increasingly common in recent years and are particularly useful for carrying trailers and containers. Articulated cars of this type include a series of car units, the outermost ends of the end units having conventional couplers and trucks, and the intermediate ends having semi-permanent articulated connections and trucks that are common to two adjacent ends. U.S. Pat. Nos. 4,233,909 and 4,346,790 show cars of this nature.
Federal regulations and the railway industry require that railway cars be equipped with handbrakes, and that the braking force be at least 11% of the total weight of the loaded car. For articulated cars, it would be expensive and inconvenient to place a handbrake on every unit, but at the same time a handbrake for two trucks of only one unit could not apply the required braking force.
To overcome these problems, the construction described in U.S. Pat. No. 4,346,790 includes a single handbrake wheel which is connected by chains and rods to operate brakes on three trucks of a car. While a system of this nature may be able to satisfy the braking force requirement, it has two important disadvantages. First, the interconnections, as shown in the patent, between the brakes of the multiple trucks raises the possibility that a jam at one point in the brake system may prevent movement of the rods and make the entire handbrake system inoperable. Second, the system operates the brakes of three trucks but requires two automatic slack adjusters, which makes the system relatively expensive.
It is a general object of the present invention to provide an improved handbrake system which avoids the foregoing problems.